A cylinder with 15 mm radius, contains an electric resistance heater, is located in an oil of temperature 30 °C, the power per unit length required to maintain a uniform surface temperature of 100 °C is 30 KW/m. Then the convection coefficient is:

A cylinder with 15 mm radius, contains an electric resistance heater, is located in an oil of temperature 30 °C, the power per unit length required to maintain a uniform surface temperature of 100 °C is 30 KW/m. Then the convection coefficient is:

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.64P: The interior wall of a large, commercial walk-in type meat freezer is covered under normal operating...

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Radiation

Radiation can be described as the energy in the form of a particular matter or electromagnetic waves traveling in the air and can be in the form of light, sound, and heat. Radiation can be detected through special instruments like X-rays. The radiation from a cooler object is less intense as compared to the radiation from hot objects.

Question

A cylinder with 15 mm radius, contains
an electric resistance heater, is located
in an oil of temperature 30 °C, the power
per unit length required to maintain a
uniform surface temperature of 100 °C
is 30 KW/m. Then the convection
coefficient is:
Select one:
a. 4.55 W/m2.K
b. 4.55 W/m.K
c. 5.45 W/m2.K
d. 4.45 W/m.K
e. None of the mentioned

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